Anyone who has picked up a games controller in the past few years has marvelled at the impeccably detailed realism of the virtual cities in Bioshock, Grand Theft Auto, Assassin's Creed and many more. But from SimCity to Minecraft, many of us have also made our own cities – labours of love that teach us it's not always easy to be a godlike mayor.

Following our piece on what video games can teach us about cities, we want to hear your favourite virtual places – from a beautiful view in GTA to that 20-million-strong SimCity megalopolis you've been building (or possibly destroying). What are the best game cities to live in? The worst? Perhaps you've designed one you think would be better than your own city?

Let's hear your thoughts – tell us in the comments below, or share your screengrabs using GuardianWitness. Just click on the blue 'Contribute' button, or if you're out and about you can download the free GuardianWitness app for smartphones.

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